• Steel and Composite Structures
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• 제17권4호
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• pp.387-403
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• 2014

This paper presents a high accuracy Finite Element approach for delamination modelling in laminated composite structures. This approach uses multi-layered shell element and cohesive zone modelling to handle the mechanical properties and damages characteristics of a laminated composite plate under low velocity impact. Both intralaminar and interlaminar failure modes, which are usually observed in laminated composite materials under impact loading, were addressed. The detail of modelling, energy absorption mechanisms, and comparison of simulation results with experimental test data were discussed in detail. The presented approach was applied for various models and simulation time was found remarkably inexpensive. In addition, the results were found to be in good agreement with the corresponding results of experimental data. Considering simulation time and results accuracy, this approach addresses an efficient technique for delamination modelling, and it could be followed by other researchers for damage analysis of laminated composite material structures subjected to dynamic impact loading.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.77-86
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• 2004

Since world container throughput continues to grow, the main issues facing decision-makers at port container terminals are how to expand the existing container terminals and construct new container terminals. Simulations can be used in the decision making process tools due to its ease and ability to reflect the real world system. The object-oriented approach provides for both reusability and modularity that best fits these requirements. In this paper, the object-oriented approach to modeling and simulating general container terminals is presented. Simulation tools based on Visual C++ provide a user-friendly input and output environment through the use of an object class-library. This paper also presents the case study of a simulation of a real container terminal in Pusan, Korea.

• 한국항공우주학회지
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• 제49권7호
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• pp.557-564
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• 2021

본 논문에서는 고정익 무인기의 점항법을 이용한 자동 착륙 접근 유도에 대해 기술한다. 본 연구의 주요 특징은 Dubin's 모델 기반 2D 사전 시뮬레이션을 이용하여 자동 착륙 접근에 필요한 경로점을 생성하고, 또한 사전 시뮬레이션으로부터 활주로까지의 남은 시간을 예측하여 이를 고도 제어에 활용한다. 설계한 알고리즘의 성능은 시뮬레이션과 비행 시험을 통해 검증한다.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1999년도 추계학술대회 논문집
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• pp.278-283
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• 1999

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.638-642
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• 1994

The objectives of this work are to present the dynamic simulation strategy based on cluster-modular approach and to develop a prototype simulator. In addition, methods for the improvement of computational efficiency and applicability are studied. A process can be decomposed into several clusters which consist of strongly coupled units depending upon the process dynamics or topology. The combined approach of simultaneous and sequential simulation based on the cluster structure is implemented within the developed dynamic process simulator, MOSA(Multi Objective Simulation Architecture). Dynamic simulation for a utility plant is presented as a case study in order to prove the efficiency and flexibility of MOSA.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.488-491
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• 1997

In this paper, a ncw control 'ialvc which can misc air-iraksge pneumatically and compensate pressure drop for an alrho~ st system uas proposed A new control valve called "Pneuniatic C70ntro1 Valve (PCV)" functions as a control valve to compcns;ltc prcssure in thc casc of air-leakage. by using the pure pneummatic control ofpilot pressure. Based on the sirnulation of the proposed PCY, thc experimental system was fabricaied su as to illustrate the efficient pcrformance of the proposed PCV with anti-leakage. Such good perfo~manccs of PCV in the air-hoist system are shown by the simulation. In addition, the simulation bascd design approach presented in this paper can be applied to any hydraulic or pneumatic-hydraulic system.

• 소성∙가공
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• 제15권3호
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• pp.189-194
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• 2006

In this paper, an automated adaptive mesh generation scheme, based on an advancing-front-Delaunay method, is presented fur finite element simulation of three dimensional bulk metal farming processes. Basic approach is introduced in detail, including a surface meshing and volume meshing technique and a mesh density control scheme. The presented approach is applied to automatic forging simulation in order to evaluate the effect of the developed schemes. Comparison shows a good agreement between required mesh density and generated mesh density, implying that the presented approach is appropriate for automatic mesh generation in metal forming simulation.

• 소성∙가공
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• 제8권2호
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• pp.216-221
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• 1999

In this paper, an application-oriented approach to piercing analysis in automatic forging simulation by the rigid-viscoplastic finite element mehtod is presented. In the presented approach, the accumulated damage is traced and the piercing instant is determined when the accumulated damage reaches the critical damage value. A method of obtaining the critical damage value by comparing the tensile test result with the analysis one is given. The presented approach is verified by experiments and applied to automatic simulation of a sequence of 6-stage forging processes.

• 대한안전경영과학회지
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• 제13권1호
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• pp.51-58
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• 2011

The uniformity of lighting distribution on the roadway is essential factor for drivers and pedestrians's safety during nighttime in urban streets. Also, the importance of roadside trees is one of the growing concern for better citizens' health and mitigating environmental impact on the urban street. But roadway lightings and roadside trees have different design or planting standards and they are not integrated in the systemic viewpoint for better safety of users during nighttime. The purpose of this study is to propose a simulation approach which assesses lighting quality in the view of illumination uniformity distribution of roadway lighting from design step and consider the layout of roadside trees. For improving lighting quality of roadway, simulation approach is needed for assessing the impact of diverse planting situation of trees and encouraged from beginning of design step for roadway construction.

• Structural Engineering and Mechanics
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• 제3권3호
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• pp.201-213
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• 1995

At present Level 2 and importance sampling methods are the main tools used to estimate reliability of structural systems. But sometimes application of these techniques to realistic problems involves certain difficulties. In order to overcome the difficulties it is suggested to use Monte Carlo simulation in combination with two other techniques-extreme value and tail entropy approximations; an appropriate Pearson's curve is fit to represent simulation results. On the basis of this approach an algorithm and computer program for structural reliability estimation are developed. A number of specially chosen numerical examples are considered with the aim of checking the accuracy of the approach and comparing it with the Level 2 and importance sampling methods. The field of application of the approach is revealed.